Question

right after takeoff, a hot air balloon ascends at a constant rate of 400 feet per minute. now, look at the vertical intercept. what is the vertical intercept for this line? the slope is 400. the vertical intercept is \boxed{}.

Explanation:

Step1: Define vertical intercept

The vertical intercept is the elevation when time $t=0$.

Step2: Analyze initial condition

At takeoff ($t=0$), the balloon is at ground level.
<Expression>
When $t=0$, elevation $= 0$ feet
</Expression>

Answer:

0